Best approach for converting from Node<TypeA> tree to a Node<TypeB> tree?

[Keavon]

I have an rctree tree of the type TypeA, which is a type that can be easily converted to type TypeB (in my case, TypeB is just a value stored in an enum variant of TypeA). I would like to convert the whole tree over (by cloning it). I couldn't see any easy way to do this based on the documentation, unless I missed something. However this seems like a commonly needed action. If it's not a built-in feature, what code should I write to make a function that performs this conversion?

[RazrFalcon]

You want to keep a tree structure, but replace values?

[Keavon]

Correct, I want to keep the existing tree structure.

[RazrFalcon]

You have to do this manually. There is no function that does this.

[Keavon]

Could you suggest an approach for the algorithm that best utilizes what's provided by the library, such as one of the different types of iterators? I'm kind of at a loss while trying to design the pseudocode taking into account the features of the library.

[RazrFalcon]

I was wrong. It's not possible. Node's data is generic, so you cannot swap it.

The only solution is to store enum instead and change it via Node::borrow_mut.

[Keavon]

I was able to implement this with the following code:

fn type_b_from_type_a(a: &rctree::Node<TypeA>) -> rctree::Node<TypeB> {
    let b = match &*a.borrow() {
        TypeA::CaseWithTypeB(node) => node.clone(),
        _ => panic!(),
    };

    let mut tree_result = rctree::Node::new(b);

    for tree_node in a.children() {
        tree_result.append(type_b_from_type_a(&tree_node));
    }

    tree_result
}